{
 "report": "Lahore's smog: the year-round baseline, and what changes in October",
 "published": "2026-11-02",
 "centre": {
  "lat": 31.55,
  "lon": 74.34,
  "name": "central Lahore"
 },
 "evidence": [
  {
   "id": "ground_october",
   "claim": "PAQI: Lahore October mean PM2.5 136.3 (2025) -> 100.1 µg/m³ (2026), -27%, at 26 sites reporting in both years; PAQI model: this October's weather alone lowered PM2.5 about 19% versus last October's weather",
   "source": "PAQI analysis as reported by ProPakistani, 2 Nov 2026",
   "url": "https://propakistani.pk/2026/11/02/lahore-smog-drops-27-percent-october-weather/amp/",
   "note": "Matched-site PAQI figures, not IQAir's 124 and 100. The earlier claim of 31 days above 35 is no longer used. Counterfactual: this October's emissions under last October's weather; with typical weather in both months the gap would be about 4% (ProPakistani).",
   "status": "verified against press report; PAQI's model not reproduced"
  },
  {
   "id": "aqi_nov",
   "claim": "Lahore AQI 448 on Sunday 1 Nov 2026 (PMD sources, The Nation); IQAir US AQI 535 at 8 am on 2 Nov 2026 (Dawn)",
   "source": "The Nation, 2 Nov 2026; Dawn, 2 Nov 2026",
   "url": [
    "https://www.nation.com.pk/02-Nov-2026/lahore-ranks-polluted-city-world-aqi-reaches-hazardous-448",
    "https://www.dawn.com/news/2041584"
   ]
  },
  {
   "id": "monthly_pm25",
   "claim": "Lahore monthly mean PM2.5 (µg/m³), IQAir city history (one product, two readings)",
   "values": {
    "2025-10": 123.5,
    "2025-11": 183.4,
    "2025-12": 177.5,
    "2026-01": 124,
    "2026-02": 125.3,
    "2026-03": 67.1,
    "2026-04": 48.4,
    "2026-05": 45.5,
    "2026-06": 40,
    "2026-07": 53,
    "2026-08": 55.9,
    "2026-09": 58.6,
    "2026-10": 100.3
   },
   "limits": {
    "pakistan_24h": 35,
    "pakistan_annual": 15,
    "who_annual": 5,
    "note": "35 is a 24-hour standard shown on a monthly chart for context; monthly means can't give daily exceedance counts"
   },
   "source": "IQAir Lahore city page, Historic > Monthly. Oct 2025-Aug 2026 read 2026-09-14 (report/data/iqair-citypage-monthly-oct2025-sep2026.json); Sep-Oct 2026 read 2026-11-02T20:36Z (report/data/iqair-citypage-monthly-snapshot-2026-11-03.json); Dec 2025-Aug 2026 identical in both readings",
   "geography": "IQAir city average, Lahore",
   "units": "µg/m³, monthly mean",
   "derived": {
    "apr_sep_2026_range": [
     40,
     58.6
    ],
    "apr_sep_2026_mean": 50.2,
    "oct2025_over_aprsep": 2.46,
    "nov2025_over_aprsep": 3.65,
    "aprsep_mean_over_annual_standard_15": 3.3
   },
   "not_used": "IQAir 2025 annual-report city table (different, finalized product): Oct 123.4, Nov 183.9, Dec 171 (report/data/iqair-annual-and-2025-monthly.json). Earlier draft used Sep 45.6, which covered 1-14 Sep only.",
   "status": "corrected (Sep, Oct 2026); verified",
   "input": [
    "iqair-citypage-monthly-oct2025-sep2026.json",
    "iqair-citypage-monthly-snapshot-2026-11-03.json"
   ]
  },
  {
   "id": "mixing_height",
   "claim": "ERA5 boundary-layer height and 10 m wind at central Lahore, monthly means 2019-2025",
   "blh_m": {
    "1": 224,
    "2": 298,
    "3": 408,
    "4": 688,
    "5": 858,
    "6": 825,
    "7": 529,
    "8": 477,
    "9": 451,
    "10": 399,
    "11": 262,
    "12": 191
   },
   "wind_ms": {
    "1": 1.86,
    "2": 2.16,
    "3": 2.38,
    "4": 2.44,
    "5": 2.42,
    "6": 2.21,
    "7": 2.2,
    "8": 1.99,
    "9": 1.78,
    "10": 1.82,
    "11": 1.85,
    "12": 1.77
   },
   "october_1_26_blh_m": {
    "2019": 466,
    "2020": 430,
    "2021": 439,
    "2022": 485,
    "2023": 328,
    "2024": 410,
    "2025": 319,
    "2026": 362
   },
   "source": "ERA5 via Open-Meteo archive API (models=era5), hourly, 31.55 N 74.34 E",
   "note": "An earlier version of this report gave October wind speeds from Open-Meteo's default blended series, in km/h mislabelled as m/s; that series changes model in recent years. ERA5 alone shows no unusual October wind in 2025 or 2026."
  },
  {
   "id": "timelapse_counts",
   "claim": "Hotspot detections of all kinds, all satellites, in the frame 30.0-32.6 N, 72.4-75.9 E, per Pakistan-time day",
   "values": {
    "2026-10-01": 135,
    "2026-10-02": 212,
    "2026-10-03": 182,
    "2026-10-04": 217,
    "2026-10-05": 200,
    "2026-10-06": 318,
    "2026-10-07": 250,
    "2026-10-08": 203,
    "2026-10-09": 295,
    "2026-10-10": 351,
    "2026-10-11": 4,
    "2026-10-12": 152,
    "2026-10-13": 151,
    "2026-10-14": 217,
    "2026-10-15": 41,
    "2026-10-16": 150,
    "2026-10-17": 449,
    "2026-10-18": 826,
    "2026-10-19": 611,
    "2026-10-20": 356,
    "2026-10-21": 574,
    "2026-10-22": 656,
    "2026-10-23": 842,
    "2026-10-24": 451,
    "2026-10-25": 586,
    "2026-10-26": 686,
    "2026-10-27": 829,
    "2026-10-28": 1047,
    "2026-10-29": 1265,
    "2026-10-30": 1044,
    "2026-10-31": 1239,
    "2026-11-01": 1538
   },
   "source": "NASA FIRMS via HamariHawa /api/day",
   "definition": "All hotspot kinds (crop, kiln, urban, industrial, landfill, hotspot, forest, open, mixed), all satellites (Suomi NPP, NOAA-20, NOAA-21, MODIS Terra, MODIS Aqua), inside the rectangular frame 30.0-32.6 N, 72.4-75.9 E (no radius filter), per Pakistan-time day. crop_associated gives the subset with kind = crop for the two days quoted in the report. Processing: FIRMS VIIRS (low-confidence detections dropped) and MODIS (confidence >= 30); the same ~400 m spot seen by several satellites on one Pakistan-time day is counted once; MODIS points dropped where VIIRS saw a fire within ~1 km. Each detection is classified by kind (crop, kiln, urban, industrial, landfill, hotspot = persistent always-hot spot, forest, open, mixed); 'crop' = on farmland away from known kilns, dumps, industry and towns (an inference, not ground-checked). Detections are not deduplicated fire events, burned area or emissions; clouds and data gaps are not corrected.",
   "status": "reproduced from archive (exact match, 3 Nov 2026)",
   "crop_associated": {
    "2026-10-01": 121,
    "2026-11-01": 1490
   },
   "input": "fires-all-satellites-frame-2026-10-01-to-11-01.csv"
  },
  {
   "id": "crop_40km",
   "claim": "Crop-labelled fire spots within 40 km of central Lahore, 15 Oct-1 Nov 2026, all satellites",
   "total": 781,
   "by_district": {
    "Sheikhupura": 322,
    "Tarn Taran (IN)": 149,
    "Amritsar (IN)": 106,
    "Nankana Sahib": 77,
    "Lahore": 62,
    "Kasur": 50,
    "Gujranwala": 15
   },
   "non_crop_within_40km": {
    "total": 72,
    "urban": 21,
    "kiln": 20,
    "always-hot spot": 14,
    "near landfill": 11,
    "industrial": 5,
    "mixed": 1
   },
   "source": "HamariHawa /api/day (NASA FIRMS)",
   "definition": "Crop-associated detections only (kind = crop), all satellites, within 40 km (haversine) of central Lahore, 15 Oct-1 Nov 2026 inclusive, both sides of the border, by district. non_crop_within_40km counts the other kinds within the same radius and dates (urban, kiln, always-hot spot = kind 'hotspot', near landfill = kind 'landfill', industrial, mixed). Distances are great-circle (haversine) from 31.55 N, 74.34 E, Earth radius 6,371 km; see radius_filtering. Processing: FIRMS VIIRS (low-confidence detections dropped) and MODIS (confidence >= 30); the same ~400 m spot seen by several satellites on one Pakistan-time day is counted once; MODIS points dropped where VIIRS saw a fire within ~1 km. Each detection is classified by kind (crop, kiln, urban, industrial, landfill, hotspot = persistent always-hot spot, forest, open, mixed); 'crop' = on farmland away from known kilns, dumps, industry and towns (an inference, not ground-checked). Detections are not deduplicated fire events, burned area or emissions; clouds and data gaps are not corrected.",
   "status": "reproduced from archive (exact match, 3 Nov 2026)",
   "input": "fires-all-satellites-frame-2026-10-01-to-11-01.csv",
   "radius_filtering": "see radius_filtering at top level"
  },
  {
   "id": "crop_100km",
   "claim": "Crop-labelled fire spots within 100 km of central Lahore, 15 Oct-1 Nov 2026",
   "total": 7130,
   "pakistan": 4759,
   "india": 2371,
   "source": "HamariHawa /api/day (NASA FIRMS)",
   "definition": "Crop-associated detections only (kind = crop), all satellites, within 100 km (haversine) of central Lahore, 15 Oct-1 Nov 2026 inclusive; pakistan/india split by the country of the detection's district. Distances are great-circle (haversine) from 31.55 N, 74.34 E, Earth radius 6,371 km; see radius_filtering. Processing: FIRMS VIIRS (low-confidence detections dropped) and MODIS (confidence >= 30); the same ~400 m spot seen by several satellites on one Pakistan-time day is counted once; MODIS points dropped where VIIRS saw a fire within ~1 km. Each detection is classified by kind (crop, kiln, urban, industrial, landfill, hotspot = persistent always-hot spot, forest, open, mixed); 'crop' = on farmland away from known kilns, dumps, industry and towns (an inference, not ground-checked). Detections are not deduplicated fire events, burned area or emissions; clouds and data gaps are not corrected.",
   "status": "reproduced from archive (exact match, 3 Nov 2026)",
   "input": "fires-all-satellites-frame-2026-10-01-to-11-01.csv",
   "radius_filtering": "see radius_filtering at top level"
  },
  {
   "id": "crop_seasons",
   "claim": "NOAA-20 crop-fire spots within 100 km of central Lahore, Pakistani side, by period: 1-14 Oct, 15 Oct-1 Nov, 2-15 Nov, 16-30 Nov",
   "values": {
    "2019": [
     262,
     812,
     571,
     1287
    ],
    "2020": [
     1032,
     970,
     1309,
     803
    ],
    "2021": [
     934,
     3139,
     2749,
     779
    ],
    "2022": [
     483,
     1622,
     1203,
     713
    ],
    "2023": [
     897,
     622,
     1073,
     765
    ],
    "2024": [
     831,
     1925,
     1261,
     508
    ],
    "2025": [
     372,
     2193,
     1337,
     165
    ],
    "2026": [
     508,
     1654,
     null,
     null
    ]
   },
   "source": "HamariHawa archive (NASA FIRMS)",
   "definition": "NOAA-20 only (VIIRS, low confidence dropped; no MODIS and no other VIIRS satellite), crop-associated detections (kind = crop), districts in Pakistan only, within 100 km (haversine) of central Lahore; periods 1-14 Oct, 15 Oct-1 Nov, 2-15 Nov, 16-30 Nov, Pakistan time; the same ~400 m spot on one day counted once. after_1_nov_share_pct = (2-15 Nov + 16-30 Nov) / 1 Oct-30 Nov total. Distances are great-circle (haversine) from 31.55 N, 74.34 E, Earth radius 6,371 km; see radius_filtering. Kinds as in timelapse_counts; not fire events, burned area or emissions.",
   "status": "reproduced from archive (exact match, 3 Nov 2026)",
   "derived": {
    "2026_vs_2025_pct": -24.58,
    "2026_vs_2024_pct": -14.08,
    "after_1_nov_share_pct": {
     "2019": 63.4,
     "2020": 51.3,
     "2021": 46.4,
     "2022": 47.6,
     "2023": 54.8,
     "2024": 39.1,
     "2025": 36.9
    }
   },
   "input": "fires-noaa20-crop-pk-100km-2019-2026.csv",
   "radius_filtering": "see radius_filtering at top level"
  },
  {
   "id": "indian_punjab_peak",
   "claim": "Indian Punjab NOAA-20 crop-fire peak day per season: 2019-11-04, 2020-11-04, 2021-11-07, 2022-11-05, 2023-11-07, 2024-11-18, 2025-11-01; 2026 busiest day so far 122 spots. Diwali: 27 Oct 2019, 14 Nov 2020, 4 Nov 2021, 24 Oct 2022, 12 Nov 2023, 31 Oct 2024, 20 Oct 2025, 8 Nov 2026",
   "source": "HamariHawa archive (NASA FIRMS)",
   "definition": "NOAA-20 only, crop-associated detections (kind = crop) in districts of Indian Punjab state (whole state, no radius filter), counted per Pakistan-time day, 1 Oct-30 Nov; the peak day is the day with the most detections (2026: archive to 2 Nov). Daily counts attached. Not fire events, burned area or emissions. Clouds and data gaps are not corrected.",
   "status": "reproduced from archive (exact match, 3 Nov 2026); Diwali dates are calendar facts, not checked against the archive",
   "note": "Detections in Indian Punjab have fallen since 2021, but NASA reports a shift to later-afternoon burning after satellite overpasses, so fewer detections need not mean less burning. No causal claim about Diwali.",
   "input": "fires-noaa20-crop-indian-punjab-daily-2019-2026.csv",
   "peak_counts": {
    "2019": 3497,
    "2020": 4165,
    "2021": 5055,
    "2022": 3813,
    "2023": 1978,
    "2024": 801,
    "2025": 279,
    "2026": 122
   }
  },
  {
   "id": "no2",
   "claim": "Tropospheric NO2, mean of 15 Oct-1 Nov, Lahore box 31.40-31.65 N 74.20-74.45 E vs farmland box 31.0-31.3 N 73.8-74.1 E",
   "values": {
    "2023": {
     "city": 6291230158730158.0,
     "rural": 3209123477350640.5,
     "ratio": 1.9604200969929695,
     "peak": 9584000000000000.0,
     "peak_at": [
      31.644,
      74.213
     ],
     "city_obs_per_px": 6.220779220779221,
     "rural_obs_per_px": 8.802884615384615,
     "near_industry_km": [
      1.5
     ],
     "near_plants": [
      [
       12.8,
       "Atlas Power Plant"
      ],
      [
       21.1,
       "Sapphire Electric Power Plant"
      ]
     ],
     "inner_p95": 5671875000000000.0
    },
    "2024": {
     "city": 6050113636363636.0,
     "rural": 3761541132478632.5,
     "ratio": 1.6084135260743433,
     "peak": 7131666666666667.0,
     "peak_at": [
      31.55,
      74.301
     ],
     "city_obs_per_px": 18.0,
     "rural_obs_per_px": 18.0,
     "near_industry_km": [
      1.6
     ],
     "near_plants": [
      [
       25.0,
       "Atlas Power Plant"
      ],
      [
       33.6,
       "Kohinoor Energy Power Plant"
      ]
     ],
     "inner_p95": 5984166666666667.0
    },
    "2025": {
     "city": 6239853896103896.0,
     "rural": 3213975694444444.5,
     "ratio": 1.9414751352631163,
     "peak": 8099722222222222.0,
     "peak_at": [
      31.55,
      74.301
     ],
     "city_obs_per_px": 18.0,
     "rural_obs_per_px": 18.0,
     "near_industry_km": [
      1.6
     ],
     "near_plants": [
      [
       25.0,
       "Atlas Power Plant"
      ],
      [
       33.6,
       "Kohinoor Energy Power Plant"
      ]
     ],
     "inner_p95": 5682500000000000.0
    },
    "2026": {
     "city": 5654981281975600.0,
     "rural": 3117219665884330.0,
     "ratio": 1.8141106139760375,
     "peak": 7245714285714286.0,
     "peak_at": [
      31.494,
      74.301
     ],
     "city_obs_per_px": 7.142857142857143,
     "rural_obs_per_px": 9.052884615384615,
     "near_industry_km": [
      3.1
     ],
     "near_plants": [
      [
       27.7,
       "Kohinoor Energy Power Plant"
      ],
      [
       29.0,
       "Atlas Power Plant"
      ]
     ],
     "inner_p95": 4792142857142857.0
    }
   },
   "source": "Copernicus Sentinel-5P TROPOMI via NASA GIBS (TROPOMI_L2_Nitrogen_Dioxide_Tropospheric_Column), processed by HamariHawa",
   "caveat": "values read back from GIBS colour bands (quantized to about one band); valid observations per city pixel about 6.2 (2023), 18 (2024), 18 (2025), 7.1 (2026): 2024-25 tiles have a markedly different coverage pattern (a value every day), cause not established; the ~10% 2026-vs-2023 difference is not treated as a trend. Imagery usable here from 2023; TROPOMI record starts 2018.",
   "units": "tropospheric NO2 column, molecules/cm²",
   "status": "arithmetic verified; product version per year not documented by GIBS layer"
  },
  {
   "id": "no2_hotspots_2026",
   "claim": "HamariHawa NO2 hotspots, 14 days to 1 Nov 2026, Pakistan: Rawalpindi 6.43, Karachi 5.82, Lahore south-centre (31.494, 74.344) 4.68 (ratio to surroundings)",
   "source": "https://hamarihawa.org/api/no2.json",
   "note": "HamariHawa relative-enrichment ranking (column vs surroundings), 14 days to 1 Nov 2026; not an official ranking of ground-level concentrations"
  },
  {
   "id": "vehicles",
   "claim": "Lahore registered vehicles 30 Sep 2024: 7,484,203 (motorcycles 5,234,187; cars 1,677,740; rickshaws 228,508; pickups/vans 130,827; tractors 68,595; buses 56,957; trucks 44,127; taxis 27,573); Punjab 24,533,994. About 15,000 heavy vehicles enter Lahore daily (traffic police via Dawn, 3 Dec 2022). Punjab 2020 road exhaust PM2.5 (kt/yr): heavy-duty and buses 17.62, motorcycles 5.78, cars 4.32, light-duty 4.25; tyre/brake 2.20, road abrasion 2.45. NOx (kt): heavy 219.3, cars 90.5, light-duty 25.3, motorcycles 3.8",
   "source": [
    "https://excise.punjab.gov.pk/system/files/STOOD%20REGISTERED%20VEHICLES%20IN%20PUNJAB%20AS%20OF%2030-SEP-2024%20web_0.pdf",
    "https://urbanunit.gov.pk/Download/publications/Files/8/2023/Emission%20Inventory%20of%20Punjab%201990-2020_FD.pdf",
    "https://www.dawn.com/news/amp/1724428"
   ],
   "derived": {
    "exhaust_pm25_kt": 31.97,
    "wear_plus_abrasion_kt": 4.65,
    "wear_share_of_total_pct": 12.7,
    "wear_additional_to_exhaust_pct": 14.5,
    "exhaust_shares_pct": {
     "heavy_duty_buses": 55.1,
     "motorcycles": 18.1,
     "cars": 13.5,
     "light_duty": 13.3
    }
   },
   "geography": "registrations: Lahore district; emissions: all of Punjab, 2020",
   "status": "verified (Excise PDF, Annex B); wording corrected",
   "note": "Registrations don't measure vehicles operating in Lahore. EMEP/EEA diesel-vs-four-stroke comparison is of technology-category factors, not a measured Lahore fleet ratio. Lahore inventory: CO about 80% of transport emission mass (not a motorcycle-specific breakdown)."
  },
  {
   "id": "fuel",
   "claim": "Euro V for imported petrol from Aug 2020 and diesel from Jan 2021; local refineries (May 2025): one Euro V, two Euro III, others high-sulphur diesel; Brownfield refinery policy (2023, amended Feb 2024 and Aug 2026): completion within five years of signing the Upgrade Agreement, extendable by cure period (max one year cumulative), force majeure, or a further one year case by case (§6.1.3.5, §6.1.4.1); ECC approved the Upgrade Agreement with a five-year completion period on 14 Sep 2026 (PID PR 146), tariff incentives seven years (§6.1.2.2); new vehicles Euro II",
   "source": [
    "https://www.dawn.com/news/1567870",
    "https://tribune.com.pk/story/2544378",
    "https://petroleum.gov.pk/SiteImage/Misc/files/Brownfield%20Refinery%20upgradation_2023%281%29.pdf",
    "https://pid.gov.pk/site/press_detail/33920",
    "https://www.app.com.pk/?p=1091461"
   ],
   "status": "corrected (was: about seven years to upgrade)",
   "note": "'Notified 10 Sep 2026' could not be confirmed from the policy or PID release"
  },
  {
   "id": "kilns",
   "claim": "Brick kilns within 25 / 50 km of central Lahore, Pakistani side",
   "values": {
    "25km": 196,
    "50km": 890
   },
   "source": "site/public/sources/kilns.json (SentinelKilnDB CC BY-NC 4.0; Brick Kiln Dataset for Pakistan's IGP Region CC BY 4.0)",
   "dedup": "two datasets merged; points within about 60 m merged (scripts/build-sources.py build_kilns); within 50 km (both sides) 1,022 points remain, 71 pairs under 100 m apart and 186 under 200 m, so a few may be duplicates",
   "note": "mapped features, not a census of operating kilns",
   "status": "corrected (was 894/197; the earlier side-assignment method could not be reproduced); deduplication imperfect",
   "side_method": "geoBoundaries PAK ADM1 polygon (point-in-polygon)",
   "input": "kilns-within-50km.csv"
  },
  {
   "id": "plants_industry",
   "claim": "Within 50 km: 7 oil/gas power plants, five to the west/north-west around Sheikhupura (Bhikki about 1,180 MW per NEPRA, Sapphire 235, Halmore 225, Atlas 214, Saba 134) and two near Raiwind (Kohinoor 131, Reshma); 181 OSM industrial areas within 50 km on the Pakistani side (214 within 50 km in total)",
   "source": "site/public/sources/city/lahore.json (OpenStreetMap); https://ppib.gov.pk/bhikki.html",
   "operational_note": "Atlas Power Limited and Saba Power Company: PPAs terminated effective 30 Sep 2024 (CPPA-G Annual Report 2025, printed p.42; Dawn 11 Oct 2024). Operating status of the others not checked; locations and contract status don't establish operation or emissions.",
   "osm_read": "October 2026",
   "status": "industrial count reproduced (181); PPA dates verified; operation not verified",
   "input": [
    "osm-power-plants-within-50km.csv",
    "osm-industrial-areas-near-lahore.csv"
   ]
  },
  {
   "id": "mehmood_booti",
   "claim": "Closed 2016; about 14 million tonnes on about 41 acres; covered with soil, vent pipes installed; LWMC: gas to be sold to industry if enough, burnt if not; as of March 2025 methane releasing slowly from vents; Lakhodair takes about 5,000 t/day",
   "source": "BBC Urdu, Umar Draz Nangiana, 24 Mar 2025",
   "url": "https://www.bbc.com/urdu/articles/cg4k93376v7o"
  },
  {
   "id": "mehmood_booti_fires",
   "claim": "NASA fire detections within 450 m of the Mehmood Booti mound centre (31.6104, 74.3847), archived Oct-Nov season days",
   "values": {
    "2019": 0,
    "2020": 1,
    "2021": 5,
    "2022": 1,
    "2023": 0,
    "2024": 0,
    "2025": 0,
    "2026": 0
   },
   "source": "HamariHawa archive (NASA FIRMS)",
   "definition": "Detections of any kind from any satellite (Suomi NPP, NOAA-20, NOAA-21, MODIS Terra, MODIS Aqua) within 450 m (haversine, Earth radius 6,371 km) of the Mehmood Booti mound centre 31.6104 N, 74.3847 E, Pakistan-time days 1 Oct-30 Nov each season (2026: 1 Oct-2 Nov, 33 days). No crop/kind filter: all seven detections found are classified 'landfill' and all are VIIRS (Suomi NPP or NOAA-20). Same archive processing (low-confidence VIIRS dropped, one detection per ~400 m spot per day). Heat seen nearby but beyond 450 m (e.g. neighbouring sites within ~1 km) is not counted here. Not fire events or emissions; clouds and data gaps are not corrected, and small, short-lived, smoke-obscured or underground fires can be missed.",
   "status": "reproduced from archive (exact match, 3 Nov 2026)",
   "input": "fires-mehmood-booti-450m-2019-2026.csv"
  },
  {
   "id": "lakhodair_surface",
   "claim": "Sentinel-2 clear passes (cloud <15%) Oct 2024-Nov 2026 over the Lakhodair dump surface (31.619-31.636 N, 74.413-74.424 E): 86; passes with any pixel B12>0.45: 5; the two large ones (21 Aug 2025, 8 Oct 2026) were clouds on inspection; the others 2-10 pixels",
   "source": "Earth Search Sentinel-2 L2A COGs, processed by HamariHawa",
   "status": "unverified count; text no longer gives a number",
   "reproduction": "The original 86 scenes were not archived. Re-listing on 3 Nov 2026 (Earth Search STAC, sentinel-2-l2a, dump box, scene-level eo:cloud_cover < 15, 1 Oct 2024-2 Nov 2026) gives 184 items on 99 distinct dates: report/data/lakhodair-s2-scenes-2026-11-03.json. Scene-level cloud cover doesn't guarantee a clear view of the site.",
   "conclusion": "No clear large surface fire identified in the usable images examined; small, short-lived, obscured or subsurface fires can be missed"
  },
  {
   "id": "lakhodair_methane",
   "claim": "Carbon Mapper source record, Lakhodair: persistence-adjusted source emission estimate 1,559.3 kg CH4/h, reported uncertainty 438.3 kg/h (confidence level not stated); 19 plumes; detected on 11 of 12 observed dates (persistence 91.67%); plume detection dates 2023-06-10 to 2026-03-22. No Carbon Mapper record for Mehmood Booti",
   "source": [
    "https://api.carbonmapper.org/api/v1/catalog/sources.geojson?bbox=74.36&bbox=31.59&bbox=74.44&bbox=31.65",
    "https://carbonmapper.org/articles/product-guide"
   ],
   "note": "Carbon Mapper persistence-adjusted source estimate combining emission rates by observation date; not a continuous whole-landfill measurement. Not all detected plumes necessarily have quantified rates; uncertainty confidence level not stated.",
   "status": "corrected wording",
   "derived": {
    "avg_emission_auto_kg_h": 1701.05,
    "times_persistence": 0.91667,
    "equals": 1559.3
   },
   "input": "carbonmapper-lakhodair-2026-11-02.geojson"
  },
  {
   "id": "dust",
   "claim": "CAMS global (Open-Meteo 'dust' = aermr06, largest dust bin, particle radii 0.9-20 µm (ECMWF param 210006; radii per ECMWF forum), not total dust) daily mean >= 50 µg/m³ at 31.55 N 74.34 E on 9 days in Oct 2026 (1-3, 7-11, 30 Oct); modelled PM2.5 averaged 65.30 µg/m³ on those days and 67.67 on the other 22",
   "method": "hourly values, averaged by Pakistan-time day (timezone Asia/Karachi), 24 hours per day",
   "source": "Open-Meteo air-quality API, domains=cams_global, read 3 Nov 2026 (report/data/cams-lahore-oct2026-hourly.json); field mapping: open-meteo Sources/App/Cams/CamsDomain.swift; https://codes.ecmwf.int/grib/param-db/210006",
   "removed": "'dust about 40-44% of modelled PM10' (one size bin is not a dust-PM10 fraction); causal conclusions about dust and AQI",
   "status": "verified (recomputed); interpretation corrected",
   "pm10_definition": "PM10 includes particles with aerodynamic diameters up to about 10 µm, including PM2.5",
   "input": "cams-lahore-oct2026-hourly.json"
  },
  {
   "id": "inventories",
   "claim": "Urban Unit Lahore 2023 inventory (2021 data), PM2.5 t/yr: transport 397, crop burning 371, waste burning 320, industry 29, total 1,120; transport's 83% is of all pollutants summed by mass (mostly CO); notes vehicle figures may be overestimated. PAQI national landscape report (https://zenodo.org/records/17629179; Dawn, 10 Dec 2025): Lahore primary PM2.5 emissions 35% transport, 28% heavy industry, 17% brick kilns; Punjab EPA disputes its data",
   "source": [
    "https://urbanunit.gov.pk/Download/publications/Files/8/2023/Emission%20Inventory%20of%20Lahore%202023.pdf",
    "https://www.dawn.com/news/1960268"
   ],
   "note": "Emission-inventory shares, not ambient or receptor apportionment; secondary formation, transport and removal prevent direct conversion"
  },
  {
   "id": "visibility_history",
   "claim": "Share of Dec-Jan days with daily-mean visibility < 1 km, winters with >= 70% of days reported. Amritsar airport (GSOD 42071099999): 1970s 0.8%, 1980s 4.4%, 1990s 10.3%, 2000s 13.9%, 2010s 20.0%, 2020-24 41.1%. Lahore airport (41641099999) days < 1 km per Oct-Jan winter: 1992-97 0-1; 1998-99 to 2017-18 1-23",
   "source": "NOAA NCEI Global Surface Summary of the Day",
   "caveat": "unadjusted daily-mean visibility; fog, haze and smoke not separable; changing observation frequency can shift daily means",
   "geography": "Amritsar airport about 47 km from 31.55 N 74.34 E; Lahore airport about 7 km",
   "winter_label": "Amritsar: Dec of year Y + Jan of Y+1, grouped by Y; Lahore: Oct-Jan season labelled Y-(Y+1)",
   "observation_frequency": "Amritsar median readings per day: 5-7 in 1970s-80s, 6-14 in 1990s, 10-21 in 2000s, 22-24 since 2010s; series not adjusted",
   "status": "verified (recomputed); labels corrected (was 25 km)"
  },
  {
   "id": "modis_fire_history",
   "claim": "MODIS (Terra+Aqua) active-fire detections. Counts, 15 Oct-30 Nov: NE Pakistani Punjab (box 29.5-32.6 N, 72.0-76.9 E) 631/670/694 in 2002-04, 1,572/1,663/1,614/1,636 in 2022-25. Share of 1 Oct-30 Nov detections recorded in November: Indian Punjab 5/10/11% (2002-04) to 78/67/83/85/73% (2021-25); Pakistani Punjab 87/79/88% to 57/51/63/61/45%. Within 100 km of Lahore, 15 Oct-30 Nov: Indian side 2.4-5.6x Pakistani side in 2009-2020, similar in 2024-25 (950 vs 750; 793 vs 683)",
   "source": "NASA FIRMS MODIS_SP C6.1, processed by HamariHawa",
   "definition": "MODIS only (Terra + Aqua, FIRMS MODIS_SP Collection 6.1 standard product), confidence >= 30, FIRMS type 0 (presumed vegetation fire), within the box 29.5-32.6 N, 72.0-76.9 E; exact duplicate rows removed. Not classified by source (no crop/kiln/town labels, unlike the HamariHawa archive's recent counts) and not deduplicated across satellites or into individual fires. Counts compare 15 Oct-30 Nov; November shares are of 1 Oct-30 Nov, Punjab state on each side; the 100 km comparison uses haversine distance from 31.55 N, 74.34 E. Late-afternoon burning after the satellite overpasses is missed (NASA Earth Observatory). Country is assigned using boundary polygons; state/province is assigned from the nearest mapped settlement. The 2026 near-real-time row (not used in the report) covers 1 Oct to 1 Nov 2026; the cutoff is set once in firms_season.py and enforced in the analysis, so later cached observations are dropped. Fields named 15 Oct-1 Nov are restricted to that window.",
   "status": "arithmetic_only (inputs not attached)",
   "script": "scripts/reports/lahore-smog-sources/analysis/fetch_firms.py, firms_analysis.py, firms_season.py"
  },
  {
   "id": "era5_long",
   "claim": "ERA5 November mean boundary-layer height at Lahore by decade: 1980s 278 m, 1990s 298, 2000s 294, 2010s 281, 2020-25 252; Theil-Sen -7 m/decade (p 0.05); November wind about 1.85 m/s with no trend; lowest Novembers 2025 (220.0 m), 1987 (226.1), 2023 (230.9), 2016 (233.8); OLS trend -6.2 m/decade (about -10% over 1980-2025), interannual SD 29 m; November mean 10 m wind 1.86 (1980s) vs 1.88 m/s (last 10 years)",
   "source": "ERA5 via Open-Meteo (models=era5), 1980-2025",
   "note": "all-hour means, not afternoon depths; 2025 and 2023 Novembers had conditions favouring accumulation near the ground; humidity and other variables not analysed",
   "status": "corrected (ranking)"
  },
  {
   "id": "history_literature",
   "claim": "Lahore annual PM2.5 194 ± 94 µg/m³, Jan 2007-Jan 2008 (Stone et al. 2010); fog frequency regime shifts ~1990 and ~1998 over South Asia (Syed et al. 2012); Lahore district population 6.32 m (1998), 13.00 m (2023); Lahore registered vehicles ~1.95 m (2008, JICA)",
   "source": [
    "https://doi.org/10.1016/j.atmosenv.2009.12.015",
    "https://doi.org/10.1007/s00382-012-1414-0",
    "https://www.pbs.gov.pk/census-2023",
    "https://openjicareport.jica.go.jp/pdf/12068219_02.pdf"
   ],
   "note": "Stone et al. 2010: PM2.5 194 ± 94 µg/m³, samples every sixth day 12 Jan 2007-19 Jan 2008; one study, not comparable with modern network means for trends. Syed et al. 2012: 82 stations 1976-2010, fog regime shifts 1990 and 1998, alongside gradual RH rise (abstract via search snippets; publisher page blocked). Dawn 30 Dec 2008 on Suparco fog study. JICA 2012: 1.95 m motorized vehicles registered in Lahore in 2008. IRIN Dec 2006 'smog' article could not be opened, so not cited.",
   "status": "verified (Stone abstract, Dawn, JICA); Syed via abstract snippets"
  }
 ],
 "revised": "2026-11-03",
 "status_key": {
  "verified": "checked against the primary source, or recomputed from an archived input on 3 Nov 2026",
  "reproduced from archive": "recomputed exactly from HamariHawa's archived FIRMS-derived day files (extract attached); the archive's processing of raw FIRMS files was not independently re-audited",
  "corrected": "changed on 3 Nov 2026 after review",
  "arithmetic_only": "arithmetic checked; underlying observations not re-checked",
  "unverified": "not reproduced; precision removed or limitation stated"
 },
 "version": "2026-11-03e",
 "inputs": {
  "note": "Extracts sent with the PDF (folder HamariHawa-Lahore-smog-data-3-Nov-2026) and kept in the repo under report/data/",
  "files": {
   "fires-noaa20-crop-pk-100km-2019-2026.csv": "every NOAA-20 crop-associated detection on the Pakistani side within 100 km of 31.55 N 74.34 E, 1 Oct-30 Nov 2019-2025 and 1 Oct-2 Nov 2026 (reproduces crop_seasons)",
   "fires-all-satellites-frame-2026-10-01-to-11-01.csv": "every detection, all satellites and kinds, in the frame 30.0-32.6 N 72.4-75.9 E, 1 Oct-1 Nov 2026 (reproduces timelapse_counts, crop_40km, crop_100km, non-crop counts)",
   "kilns-within-50km.csv": "merged kiln points within 50 km, with side (geoBoundaries PAK ADM1 polygon)",
   "osm-industrial-areas-near-lahore.csv": "OpenStreetMap industrial areas, distance and side",
   "osm-power-plants-within-50km.csv": "OpenStreetMap power plants within 50 km",
   "iqair-citypage-monthly-oct2025-sep2026.json": "IQAir city history read 14 Sep 2026",
   "iqair-citypage-monthly-snapshot-2026-11-03.json": "IQAir city history read 2 Nov 2026 20:36 UTC",
   "iqair-annual-and-2025-monthly.json": "IQAir 2025 annual-report product (not used in chart)",
   "cams-lahore-oct2026-hourly.json": "Open-Meteo CAMS global hourly PM2.5, PM10, dust, Oct 2026",
   "carbonmapper-lakhodair-2026-11-02.geojson": "Carbon Mapper source record",
   "lakhodair-s2-scenes-2026-11-03.json": "Sentinel-2 scene list (re-listed)",
   "era5_oct_nov.csv, gsod_season_visibility.csv, gsod_split_octnov_decjan.csv, firms_season_counts.csv": "history analysis outputs (scripts in repo: scripts/reports/lahore-smog-sources/analysis/)",
   "fires-mehmood-booti-450m-2019-2026.csv": "every detection within 450 m of the Mehmood Booti mound centre, all satellites and kinds, 1 Oct-30 Nov 2019-2025 and 1 Oct-2 Nov 2026 (reproduces mehmood_booti_fires)",
   "fires-noaa20-crop-indian-punjab-daily-2019-2026.csv": "NOAA-20 crop-associated detections per Pakistan-time day in Indian Punjab state, 1 Oct-30 Nov 2019-2025 and 1 Oct-2 Nov 2026 (reproduces indian_punjab_peak)"
  }
 },
 "radius_filtering": "The km_from_31.55N_74.34E column in the fire CSVs is rounded to 0.1 km for display. To reproduce the reported counts, recompute each detection's great-circle (haversine) distance from its lat/lon to 31.55 N, 74.34 E with Earth radius 6,371 km and filter on that. Filtering the rounded column directly gives different boundary counts: 785 instead of 781 within 40 km and 7,148 instead of 7,130 within 100 km (15 Oct-1 Nov 2026, kind = crop). fires-noaa20-crop-pk-100km-2019-2026.csv is already filtered to <= 100 km by haversine distance. Mehmood Booti uses the same formula from 31.6104 N, 74.3847 E."
}